To find your roof’s total square footage:
- Measure the length and width of each plane on the roof (including dormers) then multiply length times width.
- Add the square footage of each of the planes together.
How do you measure for a new roof?
To do this, measure the length and width of each plane on the roof, including dormers. Then, multiply length x width to get the square footage of each plane. Finally, calculate your roof’s total square footage by simply adding the square footage of each of the planes together.
How do you measure roofing materials?
Measure the length and width of each portion of the roof, multiply length by width for each plane, and then add the planes together for the total square footage. If you have a simple gable roof, you’ll only need to measure and sum up the 2 planes of the roof. Follow Us.
Call Us for Roof Measurements : (315) 926-1777
OR Email us : info@skyroofmeasure.com
CALCULATING THE AREA (ESTIMATED)
If you don’t want to do a lot of measuring, you can use your pitch calculation to get an estimated square footage of your roof:
- Once you have your roof’s pitch, divide the number by 12. (For example, if your roof’s pitch is 4 in 12, you would divide 4 by 12. This would yield 1/3.)
- Next, square your result. (If your number is 1/3, squared would yield 1/9.)
- After that, add 1 to your number. (1/9 + 1 = 10/9.)
- Next, figure out the square root of your new number. (The square root of 10/9 is 1.05.)
- Determine the square footage of one floor of your home. (For example, if you have a two-story home that’s 2,600 square feet, one floor would be 1,300 square feet.)
- Multiply this number by your most recent result to get the estimated square footage of your roof. (1,300 x 1.05 = 1,365 square feet.)
CALCULATING THE AREA (TRUE)
If you want to get the exact area measurement for your roof, you can follow these steps:
- Once you have your roof’s pitch, divide the number by 12. (For example, if your roof’s pitch is 4 in 12, you would divide 4 by 12. This would yield 1/3.)
- Next, square your result. (If your number is 1/3, squared would yield 1/9.)
- After that, add 1 to your number. (1/9 + 1 = 10/9.)
- Next, figure out the square root of your new number. (The square root of 10/9 is 1.05.)
- Next, use your measuring tape to measure the length of your house. (Be sure to include overhangs.)
- After that, measure the width of your house. (Be sure to include overhangs.)
- Multiply your house length by your house width to get the area. (For example, 40 feet x 30 feet = 1,200 square feet.)
- Next, multiply the area by your roof’s pitch. (1,200 x 1.05 = 1,260 square feet.)
- To allow for hips, ridges, and waste, add 10% of your final number for a gable roof and 17% of your final number for a cottage roof. (Your total number would be either 1,386 or 1,474 square feet.)
Method 2
Determine the roof area by using a mathematical formula that accounts for the roof length, total span, and roof pitch:
- Determine your roof pitch by using a pitch gauge (available at most home improvement stores) or a smartphone app (available free through any app store).
- Measure the length of the roof surface, including overhangs.
- Measure the span of the roof, including overhangs.
- Multiply the length x the span. The result will be the plane area. Use the chart below to calculate the total area of the roof.
- Calculate the total roof area – Plane Area x Correction Factor = Roof Area
